John Calvin Commentary Isaiah 48:8

"Yea, thou heardest not; yea, thou knewest not; yea, from of old thine ear was not opened: for I knew that thou didst deal very treacherously, and wast called a transgressor from the womb." — Isaiah 48:8 (ASV)

I knew that by transgressing you would transgress. By these words, the Lord means that it is not without good reason that he so earnestly persuades and entreats the people to acknowledge that it was by him that they were chastised and afterwards delivered from such great distresses. The rebelliousness of that people might have prompted them to complain that it was useless to repeat this so often and to press it on their attention. The Prophet replies that people need not wonder at it, because he has to deal with obstinate men; and thus he confirms by different words what he said a little earlier about the iron sinew of their neck (Isaiah 48:4). The meaning amounts to this: The stubbornness of that nation was well known to God. Consequently, he left nothing undone that was suited to retain those who were attached to his service. And, having received abundant evidence from undoubted proofs, they were all the more inexcusable.

Therefore have I called you a rebel from the womb. After having torn off the mask from this nation, which, as we previously saw, falsely boasted of the name of Israel, he gives them a new name and calls them “rebels.” By the “womb” I understand to be meant not their first origin when they began to be considered a nation, but the time when they were delivered from the bondage of Egypt; for that deliverance might be regarded as a sort of nativity of the Church (Exodus 12:51). But the people, though they had experienced the infinite goodness of God, did not cease to act treacherously toward him and transgressed more and more, so that he justly calls them “rebels and transgressors.”